Electrical Adjustments; Basic Adjustments - Toshiba 19A26 Service Manual

1. BEFORE MAKING ELECTRICAL
ADJUSTMENTS
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.
CAUTION
• Use an isolation transformer when performing any service
on this chassis.
• Before removing the anode cap, discharge electricity
because it contains high voltage.
• When removing a PCB or related component, after
unfastening or changing a wire, be sure to put the wire
back in its original position.
• When you exchange IC and Transistor with a heat sink,
apply the silicon grease on the contract
section of the heat sink, Before applying new silicon
grease, remove all the old silicon grease. (Old grease
may cause damages to the IC and Transistor.)
Prepare the following measurement tools for electrical
adjustments.
1. Oscilloscope
2. Digital Voltmeter
3. Pattern Generator
On-Screen Display Adjustment
1. In the condition of NO indication on the screen.
Press the VOL. DOWN button on the set and the
Channel button (9) on the remote control for more than
2 seconds to appear the adjustment mode on the
screen as shown in Fig. 1-1.
00 OSD
2. Use the Channel UP/DOWN button or Channel button
(0-9) on the remote control to select the options shown
in Fig. 1-2.
3. Press the MENU button on the remote control to end
the adjustments.
NO. FUNCTION
00 OSD H
01 CUT OFF
04 H.VCO
05 H.PHASE
06 V.SIZE
07 V.SHIFT
08 R.DRIVE
09 B.DRIVE
10 R.BIAS
11 G.BIAS
12 B.BIAS
13 BRIGHT CENT
14 BRIGHT MAX
15 BRIGHT MIN

ELECTRICAL ADJUSTMENTS

TV
28
Fig. 1-1
NO. FUNCTION
16 CONTRAST CENT
17 CONTRAST MAX
18 CONTRAST MIN
19 COLOR CENT
20 COLOR MAX
21 COLOR MIN
22 TINT
23 SHARPNESS
24 FM LEVEL
25 LEVEL
26 SEPARATION 1
27 SEPARATION 2
28 TEST MONO
29 TEST STEREO
Fig. 1-2

2. BASIC ADJUSTMENTS

2-1: CUT OFF
1. Place the set in AV MODE without signal.
2. Using the remote control, set the brightness and contrast
to normal position.
3. Place the set in Aging Test for more than 15 minutes.
4. Activate the adjustment mode display of Fig. 1-1 and
press the channel button (01) on the remote control to
select "CUT OFF".
5. Adjust the Screen Volume until a dim raster is obtained.
2-2: FOCUS
1. Receive the monoscope pattern.
2. Turn the Focus Volume fully counterclockwise once.
3. Adjust the Focus Volume until picture is distinct.
2-3: WHITE BALANCE
NOTE: Adjust after performing CUT OFF adjustment.
1. Place the set in Aging Test for more than 15 minutes.
2. Receive the white 100% signal from the Pattern
Generator.
3. Using the remote control, set the brightness and
contrast to normal position.
4. Activate the adjustment mode display of Fig. 1-1 and
press the channel button (10) on the remote control to
select "R.BIAS".
5. Using the VOL. UP/DOWN button on the remote control,
adjust the R.BIAS.
6. Press the CH. UP/DOWN button on the remote control to
select the "R.DRIVE", "B.DRIVE", "G.BIAS" or "B.BIAS".
7. Using the VOL. UP/DOWN button on the remote control,
adjust the R.DRIVE, B.DRIVE, G.BIAS or B.BIAS.
8. Perform the above adjustments 6 and 7 until the white
color is achieved.
2-4: VERTICAL SIZE
1.
Receive the monoscope pattern from the Pattern
Generator.
2.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (06) on the remote control to
select "V.SIZE".
3.
Press the VOL. UP/DOWN button on the remote control
until the SHIFT quantity of the OVER SCAN on upside
and downside becomes 10 ± 1%.
4.
Receive a broadcast and check if the picture is normal.
D-1